Fake walls on the ask to entice people into selling into the bid. There have been a lot of those here, typically they move back as soon as they are hit.
No that is not how groups keep the price down. What they do is bid whack small amounts, sometimes even hitting below the Bid, to scare people into selling, while they sit on the Bid. Another thing they do is show a huge amount of shares just a click above the ask to make it look like a huge dump is about to take place and scare people into panic selling.
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